The present invention relates to a waste solution treating apparatus, and more particularly to an apparatus for condensing or solidifying used processing solutions in an automatic photographic processor.
An automatic photographic processing apparatus for processing photographic materials such as photographic films, photographic papers or the like comprises a processing section and a drying section; the processing section including therein a developing tank containing a developer, a silver recovery tank containing a desilvering bath such as a bleaching-fixing solution and a washing tank for rinsing in this order. An exposed photographic material, for example a photographic paper, progresses in the processing solution tanks at a predetermined proper rate by means of a conveyer comprising rollers and /or belts and then to the drying section wherein the photographic paper is blown dry.
As is well known to those skilled in the art, since the processing solutions used in the automatic photographic processor, in particular the developer and desilvering bath, deteriorate and the rinsing solution is contaminated with both the developer and the desilvering solution sticking to the photographic paper, each solution should be discarded so as to run a small but constant amount of working solution to waste in order to make room in the solution tank for sufficient replenisher. For this reason, each tank is provided with an automatic replenishment system for feeding replenishing solution into the solution tank either in doses or continuously and draining waste solution into a reservoir.
From the point of view of environmental pollution prevention, it is forbidden to throw away the waste solution in rivers. Therefore in fact traders are asked to collect the waste solution which contains silver particles. In resent years, there has been marketed a waste solution treating machine which can separate and collect solidified substances contained in the waste solution. The waste solution treating machine which can be connected to the automatic photographic processor by means of a coupling pipe, reserves temporarily the waste solution in a reservoir and then feed it to a transferring reservoir provided with a transferring roller rotatably mounted thereon. The transferring roller which is partly sunk in the waste solution reserved in the transferring reservoir transfers the waste solution onto a rotary heat roller so as to dehydrate. Solid substances as harmfull residua remaining on the outer surface of the rotary heat roller are scraped by means of a scraper and collected in a slag collecting box, while the gasified components are fed to a gas-water separator in order to separate moisture from the gas. The gas separated in the gas-water separator is discharged into the air and the water remaining in the gas-water separator is discharged into a river.
A problem of the above-described waste solution treating machine is the provision of a heater in association with the rotary heat roller for condensing and/or solidifying partly the waste solution not only because of consuming much electricity but also because of a high cost of maintenance.
Another problem is that the above-described waste solution treating machine must be separately from the automatic photographic processor and is disadvantageously high in installing cost.